Power can be generated from wind using kites to pull out a line from a power extractor such as generator. However, eventually the line must be recovered and the kite pulled in. In order to have a net power gain, the power extracted from the line being pulled out needs to be greater than the energy expended in pulling the line back in. In addition, factors such as wind speed incident on the kite, line strength, and power extractor characteristics all influence how the power is extracted from the system and what a suitable operating point should be.